Added tests for clearing chat sessions on lost connection

tests/ui/stub_ui.c

@@ -31,6 +31,12 @@ expect_cons_show_error(char *expected)
     expect_string(cons_show_error, output, expected);
 }
 
+void
+expect_any_cons_show_error(void)
+{
+    expect_any(cons_show_error, output);
+}
+
 void
 expect_ui_current_print_line(char *message)
 {